Production of high bulk yarns



Jan. 19, 1965 Y. DE MONCUIT ETAL 3,155,881

PRODUCTION OF HIGH BULK YARNS Filed Jan. 31, 1961 INVENTOR YVES de MONCUII: HENRI CROUZET ATTORNEY United States Patent 3,165,881 PRGDUQTIGN OF HIGH BULK YIS Yves de Moncuit, Chavanoz, Isere, and Henri Cronzet,

Roanne, Loire, France Filed ian. 31, 1961, Ser. No. 86,141 Claims priority, application France Feb. 3, 1969 6 Claims. (Cl. 57-34) This invention relates to improvements in the production of high bulk yarns.

One process for the production of high bulk yarns, which has come into great prominence since the advent of synthetic textiles which can be heat-set, consists in highly twisting the yarns, heat-setting them in the twisted state and then untwisting them. This imparts a threedirnensional curl to the individual filaments and gives the yarn high bulk or voluminosity. The process may be carried out using one of two methods:

(a) A discontinuous method in which the yarns are twisted, are set and are untwisted, all in separate operations, and

(b) A continuous method in which the yarns are carried through a heat-setting zone and then through a false twister so arranged that the false twist runs back along the yarn into the heat-setting zone.

This latter method, for economic reasons, is tending more and more to displace the former.

The products, in addition to having high bulk, have a high elastic elongation, i.e. the filaments may be straightened by applying tension but recover their curl on release of tension. While in hosiery, for example, this high elastic elongation presents a very considerable advantage, in other applications, notably in the knitting of sweaters and in weaving, the high bulk is still very desirable but the high elastic extension is disadvantageous.

A further heat treatment of the high bulk yarn mitigates this disadvantage. The further heat treatment may be applied while stretching the yarn or the yarn may be further heated and then wound under low tension so as to permit a substantial contraction.

The present invention is concerned with a machine which enables the Whole operation of false twisting, heatsetting and further heating to be carried out in a single run of the yarn and moreover enables the further heating to be effected either under stretching conditions or under low tension so as to permit contraction.

The machine according to the present invention comprises a frame carrying for each yarn two heating elements and a false twisting spindle between the two heating elements, the false twisting spindle being constructed and mounted so that the false twist runs back into the heating zone of the first heating element and carrying feed devices in front of each heating element and behind the second heating element, the relative speeds of the three feed devices being adjustable.

The first heating element, and most advantageously both, is provided with a heating surface which is convex in the direction of travel of the yarn. The heating surface may take the form of a convex tube and the metal of the tube or other heating surface may itself constitute an electrical resistance element for providing the heat.

Preferably the elements of the machine are mounted one above the other on the frame so that the general irection of travel of the yarn is vertically upwards. Furice ther, two banks of such vertically arranged elements are preferably fixed back to back on one frame.

In a modification of the above machine, a single yarn heater is provided to performthe double function of heat-setting and after-heating, guides being provided to return the yarn for its second passage past or through the heating element. As in the machine described above, three feed devices must be provided and be adjustable in speed relative to each other, one to feed the yarn into the heater at a predetermined speed, a second to feed the yarn coming from the false twister after its first passage through the heating zone and a third to'feed the yarn after its second passage through the heating zone. Preferably in this modified machine, the two passages of the yarn through the heating zone are in the same direction and the guides are positioned so as to feed the yarn, coming from the outlet of the heater after its first passage, back to the inlet of the heater by a path exterior to the heater. 7

The heating element in the modified machine may, if desired, be provided with grooves or, in the case of a tubular heater, with a partition to keep the yarn separate in its two passages. Alternatively a tubular heater may be constructed with two tubular passages therethrough which are integral with each other so as to equalize the heat.

Broadly therefore the invention, including this modification, comprises a frame carrying for each yarn a heating element and downstream of'the heater a false twisting spindle so constructed and mounted that the false twist runs back into the heating zone, a second heating element downstream of the false twister or guide means for guiding the yarn a second time through the heating zone and three feed devices for controlling the speed of the yarn to and from each passage through a heating zone, the relative speeds of the feeddevices being adjustable.

The invention further comprises the combination of a voluminizing frame, as described above, with a creel. Such a creel may be of the magazine type,'that is to say positions are provided for two let-off packages for each yarn running through the voluminizing frame and are so disposed with respect to one another that the inner end of the yarn on one package (a tail) can be' tied to the outer end of the yarn on the other package, the packages being of the type which are unwound by pulling over the end. Further the frame of such a creel may be extended upwards and carry in itsupper part take-up devices, one for each yarn, the frame being held at the top to the frame of the voluminizing frame by suitable cross-bars. Most advantageously the combined machine is provided with a low platform between the voluminizing frame and the creel frame and the various thread guides are so mounted that the yarns pass from the let-off packages under the platform, up through the elements of the voluminizing frame andback overhead to the take-up devices mounted in the upper part of the creel, thus enabling operatives on the platform to thread up or otherwise attend to the creel or to the voluminizing frame without interfering with the continuity of the process.

Where, as is preferred, the voluminizing frame has two banks of elements back to back, the machine is providcd with two creels, one on each side of the voluaninizing frame.

The preferred embodiment having two separate heaters is illustrated diagrammatically in the accompanying drawing, one side only of a double-sided machine being shown. Further the present description follows one yarn only through the machine, the run of the other yarns being exactly similar apart from the different positions of the let-off packages and take-up devices.

The let-off and take-up creels, shown on the right hand side of the drawing, are carried by a single frame represented by uprights 1 and 2. The lower half of the frame carries the let-off creel which is of the magazine type and carries two spindles for each yarn running through the machine. The supply packages 4 of lightly twisted or untwisted yarn are wound on tubes 3 for pulling off over end, the tubes being mounted on the spindles. The reserve packages are situated behind the packages shown in the drawing.

From the supply package 4 each yarn 5 is drawn through a thread guide 8 and a tensioning device 9 both carried by a support 7, the supports 7 being mounted in groups on rods 6. Thence the yarns travel to a further series of guides 1i) mounted in line on supports 11 at a level'below that of the platform 13. The yarns then pass underneath the platform 13 and between its supporting uprights 12. For ease of threading up, the platform is provided with slots through which the yarns are passed to their running position below the platform.

The voluminizing frame is represented by uprights 14 carrying the various elements to be referred to. Each yarn 5 coming from the let-off creel is drawn through a guide 16 by means of a positively driven feed device 17, preferably of the type described in British specification No. 809,749. From the feed device 17 the yarn passes into a convex tubular heating element, 18, the metal of which constitutes an electrical resistance through which a current is passed to generate the heat. The yarn passes thence through a false twisting device comprising a support 21 and spindle 22 with a manipulating hook 22a mounted on a detachable support 19, 2!}.

The yarn then passes to the second driven feed device i 23, preferably of the same type as feed device 17, the speed of which is adjustable to allow a predetermined shrinkage in the yarn, the shrinkage permitted being dependent upon the count of the yarn, the speed of the false twist spindle in relation to the linear speed of the yarn, the temperature of the heating element 18 and the chemical nature of the yarn.

From the feed device 23, the yarn is drawn by means of the third driven feed device 25, again preferably of the same type as feed device 17, through second heating element 24, which is preferably also of the convex tubular resistance type referred to above. The temperature of the second heat treatment is preferably lower than that of the first heat treatment, a relationship which is not readily obtained in the modified machines described above provided with. a single heater. The two heaters 18 and 24 are provided with means for accurate temperature control and especially one where the maximum variation amounts to no more than about 1C. The relative speeds of the two feed devices 23 and 25 is such as to permit a substantial contraction of the yarn, particularly a contraction of 1520% or more.

From the feed device 25, the yarn 5 passes to thread guide 26, whence it passes overhead to guides 27, 28 and to traversing guide 29 for winding on package support 31, surface driven by driving roller 30, the package building up to the form 31:: shown in dash-dot lines. The drive for the driving rollers 30 and for the traversing guides 29 may be derived, for example through chain and sprocket transmission, from the main drive used to actuate feed devices 17, 23 and 25.

The frame 1, 2 of the combined let-off creel and winding machine may be braced to the frame 14 of the voluminizing section by cross members 32.

While as described above the heating elements are constituted by convex metal tubes acting as electrical resistances, other forms of heater may be used, for example straight heated tubes or casings filled with hot air.

The invention, particularly in the form illustrated in which the yarn is caused to travel a substantially vertical path through the various elements of the voluminizing frame, provides a highly compact, readily accessible and highly efficient machine, capable of producing large packages of uniformly voluminized yarns, for example packages weighing 2 kilograms or more.

While the invention has been described in detail with reference to a preferred embodiment, it will be understood by those skilled in the art that it is capable of various modifications and improvements without departing from the scope and spirit thereof. Accordingly, the invention is not to be limited by the particular illustrative embodiment, but only by the scope of the appended claims.

That which is claimed is:

l. Yarn processing apparatus comprising a false twisting and yarn heating assembly for twisting and heat treating yarn, a yarn supply and take-up assembly disposed laterally to one side of said false twisting and heating assembly, said yarn supply and take-up assembly comprising yarn supply support means and yarn take-up means, and an intermediate operator supporting platform disposed between said assemblies, said platform having a supporting surface and a yarn passageway beneath said surface for passage of yarn between said assemblies while permitting an operator to stand on said platform without hindrance to the passage of yarn between said assemblies.

2. Apparatus according to claim 1 wherein said yarn supply support means and take-up means are disposed one above the other.

3. Apparatus comprising a double-sided yarn voluminiziing frame, two yarn supply creel frames for said voluminizing frame, a respective one of said yarn supply creel frames being disposed on each side of said voluminizing frame, each of said creel frames carrying yarn take-up devices and being adapted to carry yarn supply packages in yarn supply relation to said voluminizing frame, and an intermediate operator support platform disposed between each of the yarn supply frames and the yarn voluminizing frame, said platforms having supporting surfaces and yarn passageways beneath said surfaces for passage of yarn between said supply frames and the voluminizing frame, thus permitting an operator to stand on said platform without hindrance to the passage of yarn between said supply frames and the voluminizing frame.

4. Apparatus comprising a yarn voluminiz-ing frame and a creel frame each carrying thread guides, said creel frame being disposed beside the voluminizing frame, said voluminizing frame carrying a false twisting and yarn heating assembly for twisting and heat setting twist within a yarn, and said creel frame carrying both yarn supply and yarn take-up means, suitable cross-bars holding to.- gether the overhead sides of said frames, and a platform disposed between the lower sides of said frames, said platform providing an operator supporting surface and passageway beneath said surface so that yarn can travel in a cyclic path from the yarn supply under the platform along the voluminizing frame and across the overhead sides of said frames to take-up.

5. Apparatus according to claim 4 wherein the yarn take-up means is located above the yarn supply means so that yarn from the supply means can be cyclically fed underneath the operatorsupport surface of the platform, upwardly and vertically through the guides and false twisting and yarn heating assembly located on the v0- luminizing frame, and then across the overhead sides of said frames to the yarn take-up means.

6. Apparatus according to claim 5 wherein the false twisting and yarn heating assembly includes a pair of 2,864,229 Seem et a1. Dec. 16, 1958 convex tubular heaters, a false twist spindle disposed 2,891,376 Stoddard et a1. June 23, 1959 between said pair of heaters, and located in front of each 3,058,291 Heberlein et a1 Oct. 16, 1962 heater adjustable yarn feed devices and a third yam feed 3,067,563 Van Dijk Dec. 11, 1962 device behind the second heater, as determined by the 5 3,077,724 Stcddard et a1. Feb. 19, 1963 yarn flow relatlon. FOREIGN PATENTS RQEEI'EHQQS CiiEfi the file Of this Patent 219 270 Australia Dac. 5 1 5 UNITED STATES PATENTS 220,749 Australia Feb. 16, 1959 2,624,934 Munson et a1 Jan. 13, 1953 787,619 feat i D69 11, 1957 2,803,105 Stoddard et a1. Aug. 20, 1957 10 897,516 Great Bl'ltam l 14, 1959 2,807,130 Trapido et a1. Sept. 24, 1957 850,693 Great Britain 5, 

4. APPARATUS COMPRISING A YARN VOLUMINIZING FRAME AND A CREEL FRAME EACH CARRYING THREAD GUIDES, SAID CREEL FRAME BEING DISPOSED BESIDE THE VOLUMINIZING FRAME, SAID VOLUMINIZING FRAME CARRYING A FALSE TWISTING AND YARN HEATING ASSEMBLY FOR TWISTING AND HEAT SETTING TWIST WITHIN A YARN, AND SAID CREEL FRAME CARRYING BOTH YARN SUPPLY AND YARN TAKE-UP MEANS, SUITABLE CROSS-BARS HOLDING TOGETHER THE OVERHEAD SIDES OF SAID FRAMES, AND A PLATFORM 